I have an array
[
[[R G B]
[R G B]
[R G B]]
[[R G B]
[R G B]
[R G B]]
[[R G B]
[R G B]
[R G B]]
]
and I want it in the form
[
[[R R R]
[R R R]
[R R R]]
[[G G G]
[G G G]
[G G G]]
[[B B B]
[B B B]
[B B B]]
]
How?